The instant invention relates to a support bracket for a structural truss and specifically to such a bracket which is capable of adjusting the span length of a truss.
Open web trusses are used in the construction of buildings, and typically include an upper chord, generally formed of solid dimensional lumber or of laminated veneer lumber (LVL), a lower chord formed of similar material, and an open web, generally formed of steel tubing which extends between the upper and lower chords.
Once the plans for a building structure have been approved, trusses are ordered in specific dimensions and are prefabricated to those dimensions at a manufacturing site. In some instances, the building may not be constructed to the exact dimensions as are set forth in the plans. In such situations, it is necessary to modify the dimensions of the trusses in the field, in the case where the joists are too long, or to reorder additional trusses in the event they are too short. Both of these situations result in additional time and potential additional costs.
U.S. Pat. No. 4,682,460, for an OPEN WEB STRUCTURAL SUPPORT MOUNTING BRACKET AND LENGTH ADJUSTABLE WEB MEMBER, and U.S. Pat. No. 4,745,724, for OPEN WEB STRUCTURAL SUPPORT MEMBER OF ADJUSTABLE LENGTH WITH INCREMENTAL ADJUSTMENT OF END WEB MEMBER, both address the above-identified problem. However, the bracket of the U.S. Pat. No. 4,682,460 patent provides a rather complicated extension for a web member, while the support member of the U.S. Pat. No. 4,745,724 provides adjustment only in predetermined increments.
It is an object of the present invention to overcome the drawbacks and limitations with the prior art proposals. More specifically, the invention has its objects, one or more of the following:
(1) to provide a support bracket which is infinitely adjustable within a predetermined range;
(2) the provision of a support bracket which may be easily installed in an open web truss and which provides for adjustment for both web and chord lengths while maintaining full structural supporting capability;
(3) to develop a support bracket which locks up when a vertical load is applied to the truss; and
(4) to provide a support bracket which is easily adjustable on-site, and which does not require extensive removal and reinstallation of components.